Journal of American Science, 2011;7(7) http://www.americanscience.org 783 Sequencing of Cytochrome C Oxidase Subunit I Gene of Mitochondrial DNA from Chelonia mydas in Qatar. Khaled Elmeer, Paul McCormick and Ameenah Almalki. Biotechnology Centre, Ministry of Environment, Doha Qatar. elmeer@gmail.com Abstract: DNA of Qatari C. mydas samples were successfully sequenced using the Folmer forward and reverse primers. The identification with BOLD of approximately 688 base pairs sequence revealed maximum homology (99.84%) with C. mydas , which is a species of turtle has been declared “extinct in wild” by IUCN. The next closest species 93.79% , was N. depressa which has a restricted geographical distribution and was reported to be endemic to the Australian continental shelf. The finding of characteristic species-specific COI sequences offers the prospect of identifying marine turtle species by using DNA barcode methodology as an auxiliary tool for taxonomy. This can also be used during field work when identifying lost nests, animals stranded on beaches or those killed as part of catching in fishery nets. A further use is in forensic litigation when turtle eggs or meat are the only available material and for the development of Qatar gene bank information. [Khaled Elmeer, Paul McCormick and Ameenah Almalki. Sequencing of Cytochrome C Oxidase Subunit I Gene of Mitochondrial DNA from Chelonia mydas in Qatar.Journal of American Science 2011;7(7):783-788]. (ISSN: 1545- 1003). http://www.americanscience.org . Key word: DNA Barcoding, Green sea turtle, Cytochrome Oxidase, and COI sequencing. 1-Introduction Sea or marine turtles superfamily Chelonioidea are marine reptiles. They were on earth for over 100 million years (Hirayama, 1998), and occupy a diverse ecosystems except the Arctic poles through their throughout highly migratory life cycles (Bjorndal and Jackson, 2003). There are seven species of marine turtles in the world that include: the leatherback, Dermochelys coriacea; loggerhead, Caretta caretta; green, Chelonia mydas; flatback, Natator depressa; hawksbill, Eretmochelys imbricata; olive ridley, Lepidochelys olivacea and kemps ridley, Lepidochelys kempi (Storelli and Marcotrigiano, 2003). Of all the sea turtle species, E. imbricate along with C. mydas are the only two species found predominantly in the coral reefs of the gulf of Oman (Hossein et al., 2011). Limpus, (1995) had alarmingly reported that the number of sea turtles present in all the world's oceans is declining. The rapid decline in number of sea turtles is due to many well documented factors, most of them are due to human interactions. For example the excessive use of egg and turtle protein as food consumption and alteration of nesting, foraging habitats, mortification in marine waste, vessel strikes and incidental capture in commercial and recreational fisheries, are some of the major factors driving sea turtles toward extinction (Storelli and Marcotrigiano, 2003). To save the sea turtles from extinction, all of the clearly recognized species are listed and protected under Appendix 1 of the Convention on International Trade in Endangered Species of Fauna and Flora (CITES), so to ensure an international trade ban of the specimens of the Sea Turtles (Schouten, 1992). Furthermore, all species except N.depressa, are listed in Appendices I and II of the convention on the Conservation of Migratory Species (CMS) of wild animals (IUCN, 1995). The IUCN Red List considers C. mydas, as endangered in 1980 Bonn Convention (IUCN, 1996). The „Consortium Barcode of Life (COBOL), is an international collaborative organization whose purpose is to use “DNA barcoding” to generate a unique genetic standard barcode of every species of life on earth for taxonomic aims. The DNA barcoding is a taxonomic method that uses a short genetic marker of an organism's DNA to identify it as belonging to a particular species (Stoeckle 2003).The higher the sequencing resolution of a particular gene, the better or more accurate results in taxonomic studies. The Subunit 1 (COI or Cox1) gene is responsible for producing “Cytochrome Oxaidase C enzyme” which regulates and controls the respiratory process of the cell. Because of its unique structure and functionality from species to species, Subunit 1 (COI or Cox1) gene is therefore utilized as an accurate or optimum barcode identifier for a species. This was fully demonstrated by scientists when the Subunit (COI) gene was used to identify the North American bird species in 2004